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3102. Chapman, G.P., Peat, W.E.: An introduction to the grasses
- Creator:
- Šesták, Z.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3103. Characterisation of sphaeractinomyxon types (Cnidaria: Myxozoa) from marine and freshwater oligochaetes in a Portuguese estuary, with the demise of the endocapsa collective group
- Creator:
- Rocha, Sónia, Alves, Ängela, Antunes, Carlos, Fernandes, Pedro, Azevedo, Carlos, and Casal, Graça
- Format:
- print, počítač, and online zdroj
- Type:
- model:article and TEXT
- Subject:
- kroužkovci, Annelida, Minho (Španělsko a Portugalsko : řeka), Minho River (Spain and Portugal), Myxosporea, actinospore, life cycle, SSU rRNA gene, 2, and 59
- Language:
- English
- Description:
- Six types of sphaeractinomyxon are reported from the coelomic cavity of oligochaetes collected from the Minho River estuary in northern Portugal. Four new types are morphologically and molecularly described from freshwater species belonging to the genera Psammoryctides Hrabě and Potamothrix Vejdovský et Mrázek in the upper estuary, thus significantly increasing the number of known freshwater sphaeractinomyxon. In the lower estuary, sphaeractinomyxon types 8 and 10 of Rangel et al. (2016) are recorded infecting the marine oligochaete Tubificoides pseudogaster (Dahl). A single specimen of T. pseudogaster further displayed infection by one of the four new types found in the upper estuary, suggesting the involvement of sphaeractinomyxon in the life cycles of myxosporean species that infect migratory fish hosts. The acquisition of these second hosts is proposed to have allowed the myxosporean counterparts of sphaeractinomyxon to cross environmental barriers and conquer new habitats. Phylogenetic analyses of the SSU rRNA gene reveal the four new types clustering within the monophyletic clade of mugiliform-infecting myxobolids, strengthening the previously proposed involvement of the sphaeractinomyxon collective group in the life cycles of this specific group of myxosporeans. Endocapsa types also cluster within the latter clade, having actinospores that differ from those of sphaeractinomyxon only in the presence of valvular swellings that do not change when in contact with water. In this study, however, one type was found displaying actinospores with and without valvular swellings in the same oligochaete specimen. This overlap in actinospore morphology is given as grounds for the demise of the endocapsa collective group., Sónia Rocha, Ängela Alves, Carlos Antunes, Pedro Fernandes, Carlos Azevedo and Graça Casal., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3104. Characteristics of in vivo nitrate reduction in the CAM plant Notonia grandiflora DC.
- Creator:
- Balakumar, T., Thangavel, M., and Paliwal, K.
- Format:
- Type:
- model:internalpart and TEXT
- Language:
- Multiple languages
- Description:
- Characteristics of in vivo nitráte reductase (NR, EC 1.6.6.1) activity in leaf tissue of the crassulacean acid metabolism (CAM) plant Notonia grandiflora DC. were determined. The pH optimum for the enzyme was 7.0. Among the five low molecular mass solvents tested, n-propanol was more effective in promoting NR activity. Supply of 1.0 % (v/v) M-propanol along with 0.5 % Triton X-100 was the most appropriate assay condition to bring about maximum NR activity (NRA), that was proportionally enhanced with duration of the incubation and mass of the leaf tissue. Leaf fragments of 2 to 4 mm slice width had maximal NRA. The highest NRA was obtained with 200 mM of nitráte supplied in the infiltration medium. NRA was higher in fully expanded, mature leaves than in tender and senescing leaves. The cellular nitráte content was strongly positively correlated with NRA in leaves of various physiological ages. The NRA/N03’ content ratio (index of nitráte utilization efQciency) was the highest for the tender leaves and the lowest for the senescing leaves. However, maximum total titratable acidity (malate production) was obtained for the fully expanded mature leaves in comparison with the other leaves. A positive and significant correlation (r = 0.92) was obtained between nitráte reduction and titratable acid content. The results are indicative of a possible role of nitráte reduction in the regulation of noctumal acid production in the CAM plants.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3105. Characteristics of the compensatory renal growth of the remnant embryonic chick kidneys
- Creator:
- Klusoňová, P. and Zdeňka Zemanová
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Biochemie. Molekulární biologie. Biofyzika, fyziologie, embryologie, ledviny, physiology, embryology, kidneys, chick embryo, unilateral renal agenesis, remnant mesonephros, compensatory renal growth, DNA/protein ratio, 2, and 577
- Language:
- English
- Description:
- Growth of the remnant embryonic kidney (the mesonephros), as expressed by wet weight, was more rapid in the chick embryos with experimentally induced unilateral renal agenes is compared to controls. The difference was significant between embryonic days 8-12, when the doubled weights of remnant kidneys were increased compared with the weights of paired control kidneys. The excessive growth of the mesonephros ceased on day 14, when the normal physiological regression of the embryonic kidney begins. In the definitive kidney, the metanephros, no significant differences in weights of the control vs. remnant metanephros were found on days 10-14. The characteristics of increased mesonephric growth were evaluated by determination of DNA/protein ratios in homogenates of the kidneys. Significant cellular hypertrophy was found in both the mesonephros and metanephros of the embryos with URA on day 10. Additionally, a non-significant cellular hyperplasia was also revealed in the remnant mesonephros on day 8. This gives evidence that the growth stimuli to the mesonephroi were probably strongest between days 8-10 and that they manifested in the remnant mesonephros only. and Obsahuje bibliografii a bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3106. Characteristics of wind-induced waves in a shallow water zone
- Creator:
- Spanilá, Tamara and Jahoda, Karel
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, vlny, waves, height, length and time-period of the waves, energy of waves, 7, and 551
- Language:
- English
- Description:
- The parameters determine waves energy in shallow water zone that pronounces the crucial influence on abrasion of both natural and artificially paved banks. The effort to re-development of the relations was found as absolutely necessary for waves energy calculations. Substantial benefit of the work is found not only in enabling the use of computers while avoiding time-consuming and difficult application of diagrams, but namely in recent recognition that the calculation results showed a risk of underestimate the real impact of wind-induced waves. In some cases, the calculations respecting the above standard produce lower values of waves height and time-period and thus also lower values of wave energy., Tamara Spanilá and Karel Jahoda., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3107. Characterization and differentiation of kaolinites from selected Czech deposits using infrared spectroscopy and differential thermal analysis
- Creator:
- Lenka Vaculíková, Eva Plevová, Silvie Vallová, and Ivan Koutník
- Format:
- print, bez média, and svazek
- Type:
- article, články, model:article, and TEXT
- Subject:
- Geologie. Meteorologie. Klimatologie, infračervená spektroskopie, infrared spectroscopy, kaolinite, degree of structural order, thermogravimetry and differential thermal analysis, 7, and 551
- Language:
- English
- Description:
- This paper reports the possibilities of using FTIR spectroscopy and simultaneous thermogravimetry and differential thermal analysis for examination of the structural order of four Czech kaolinite samples (Jimlikov, Sedlec, Olomucany and Unanov deposits) and one kaolinite standard KGa-1b from Georgia deposit obtained from the Source Clays Repository of The Clay Minerals Society (USA). FTIR spectroscopy was used for the classification of the degree of structural order of kaolinite samples by empirical (IR-E) and numerical (IR-N) classification. Differential thermal analysis was used for the determination of the kaolinite disorder degree according to decomposition peak temperature obtained from DTA curves. The resulting trend of decrease in orderliness is: KGA-1b (with the best orderliness) > Jimlikov > Sedlec > Olomucany > Unanov (with the worst orderliness)., Lenka Vaculíková, Eva Plevová, Silvie Vallová and Ivan Koutník., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3108. Characterization and function of the microsporidian polar tube: a review
- Creator:
- Keohane, Elaine M. and Weiss, Louis M.
- Format:
- Type:
- model:internalpart and TEXT
- Subject:
- Microsporidia, polar tube proteins, invasion mechanism, Encephalitozoon, Glugea, and protein purification
- Language:
- English
- Description:
- Microsporidia are eukaryotic, obligate intracellular organisms defined by their small spores containing a single polar tube that coils around the interior of the spore. After appropriate stimuli the germination of spores occurs. Conditions that promote germination vary widely among species, presumably reflecting the organism’s adaptation to their host and external environment as well as preventing accidental discharge in the environment. It appears that calcium may be a key ion in this process. Regardless of the stimuli required for activation, all microsporidia exhibit the same response to the stimuli, that is, increasing the intrasporal osmotic pressure. This results in an influx of water into the spore accompanied by swelling of the polaroplasts and posterior vacuole. The polar tube then discharges from the anterior pole of the spore in an explosive reaction and is thought to form a hollow tube by a process of eversion. If the polar tube is discharged next to a cell, it can pierce the cell and transfer the sporoplasm into this cell. Polar tubes resist dissociation in detergents and acids but dissociate in dithiothreitol. We have developed a method for the purification of polar tube proteins (PTPs) using differential extraction followed by reverse phase high performance liquid chromatography (HPLC). This method was used to purify for subsequent characterization PTPs from Glugea americanus, Encephalitozoon cuniculit E. hellem and E. intestinalis. These proteins appear to be members of a protein family that demonstrate conserved characteristics in solubility, hydrophobicity, mass, proline content and immunologic epitopes. These characteristics are probably important in the function of this protein in its self assembly during the eversion of the polar tube and in providing elasticity and resiliency for sporoplasm passage.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3109. Characterization and functional analysis of the serpin-10 gene from oak silkworm, Antheraea pernyi (Lepidoptera: Saturniidae)
- Creator:
- Kausar, Saima, Qian, Cen, Abbas, Muhammad Nadeem, Zhu, Bao-Jian, Liu, Ya, Wang, Lei, Wei, Guo-Qing, Sun, Yu, and Liu, Chao-Liang
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, motýli, butterflies, Lepidoptera, Saturniidae, Antheraea pernyi, serpin, innate immunity, haemolymph protein, 2, and 59
- Language:
- English
- Description:
- Serpin is a broadly distributed superfamily of proteins that have a crucial role in regulating various immune reactions. Herein we identified a serpin-10 gene from Antheraea pernyi that encodes a 1557 amino acid residue protein with a predicted molecular weight of 58.76 kDa. Recombinant Apserpin-10 protein was expressed in a prokaryotic expression system (Escherichia coli) and the purified protein was used to prepare rabbit anti-Apserpin-10 polyclonal antibodies. Quantitative real-time polymerase chain reaction and western blot analysis indicate that Apserpin-10 was transcribed in all the tissues examined, including haemolymph, malpighian tubules, fat body, silk gland, integument and mid gut; the greatest expression level of Apserpin-10 was recorded in the fat body and haemocytes. The comparison of different developmental stages showed that Apserpin-10 transcript level was highest in 5th instar larvae, while the lowest expression was recorded at the egg stage. We also investigated the expression patterns of Apserpin-10 in fat body and haemocyte samples, following administration of heat-inactivated gram-positive bacteria (Micrococcus luteus), gram negative bacteria (Escherichia coli), a fungus (Beauveria bassiana) and virus (nuclear polyhedrosis virus, NPV). A substantial up-regulation of Apserpin-10 expression was recorded following pathogen challenge in both the tissues tested. Further the knock down of Apserpin-10 led to down regulation of antimicrobial peptide genes. Altogether, our results indicate that Apserpin-10 is involved in the innate immunity of A. pernyi., Saima Kausar, Cen Qian, Muhammad Nadeem Abbas, Bao-Jian Zhu, Ya Liu, Lei Wang, Guo-Qing Wei, Yu Sun, Chao-Liang Liu., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3110. Characterization and transcriptional analysis of a subtelomeric satellite DNA family in the ladybird beetle Henosepilachna argus (Coleoptera: Coccinellidae)
- Creator:
- Mora, Pablo, Vela, Jesús, Palomeque, Teresa, Ruiz-Mena, Areli, and Lorite, Pedro
- Format:
- print, počítač, and online zdroj
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Zoologie, brouci, slunéčkovití, transkripce, beetles, Coccinellidae, transcription, Coleoptera, Henosepilachna argus, ladybird beetle, satellite DNA, in situ hybridization, 2, and 59
- Language:
- English
- Description:
- Satellite DNAs are the major repetitive DNA components in eukaryotic genomes. Although satellite DNA has long been called "parasite DNA" there is substantial evidence that it could be associated with some functions of chromosome biology. Ladybird beetles (Coccinellidae) are one of the largest and most important groups of beetles. Many ladybirds are of economic interest as biological control agents because they eat some agricultural pests such as aphids and scale insects. However, other species are phytophagous and can damage crops. Despite the ecological importance of the latter group there are no studies on their satellite DNA. A satellite DNA family was isolated and characterized in the ladybird Henosepilachna argus. This satellite DNA is organized in tandem repeats of 658 bp and is A + T rich (67.3%). The recorded high sequence conservation of the monomers together with the detection of putative gene conversion processes indicate concerted evolution. Reverse transcription polymerase chain reaction (RT-PCR) revealed that this satellite DNA is transcribed and in situ hybridization its location in the subtelomeric regions of all chromosomes except the long arm of the X chromosome. The presence of this satellite DNA in other species of the genus Henosepilachna and Epilachna was also tested using PCR. The results indicate that this satellite DNA sequence is so far specific to H. argus., Pablo Mora, Jesús Vela, Areli Ruiz-Mena, Teresa Palomeque, Pedro Lorite., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public